Macbook Pro chimes and then switches off at boot

Hi

I have a Macbook Pro (MC374LL/A) which won't boot anymore

I followed the recommended steps in the following links:

http://support.apple.com/kb/ts2570

https://discussions.apple.com/thread/5391976

...but wasn't able to obtain any improvement

1) Safe boot doesn't work

2) Reset the NVRAM / PRAM doesn't work

3) Start up your Mac while holding the C key doesn't work

The DVD I manage to enter is immediately ejected

On each boot the grey screen lasts barely two seconds before the MBP switches itself off

Any ideas ?

thanks
yann

Try an SMC reset.

- Nick

Thanks for your help

Finally, I took the logic board out and cleaned the large amounts of dust,

removed the radiator and cleaned (all) the excess cooling paste

Treated both sides to a clear vinegar tooth brush cleanup

Reassembled and, guess what ? It works !!!

Glad to hear it's working but I would be a bit apprehensive about using any kind of vinegar since it has an acid base. I hope you finished the cleaning job with isopropyl alcohol to get rid of the left over vinegar. And I assume you re-applied Arctic Silver thermal paste to the heat sink areas?

I rinsed the board with de-mineralised water and let it dry for 24hrs in a tupperware full of dried lentils

Based on the info in the initial post...there certainly seems to have been something going on (symptoms) with this computer than was mentioned initially.

Going to the relatively extreme measure of removing the logic board & cleaning it would not have been the first thing I would have done (with the initial info given)...I would have recommended some additional troubleshooting first.

But hey...if this helped solve the problem...great! Congrats!

- Nick